The present invention relates to plumbing installations, and more particularly, to the installation of a wall mounted box for enclosing one or more valves which are rigidly mounted to a bottom wall of the box and connected to a CPVC water supply pipe in a manner that inhibits the transmission of torque to the CPVC pipe and its adhesively attached CPCV fitting, the torque resulting from manually turning a handwheel of the valve ON or OFF.
Local governing bodies typically mandate building codes, such as the Uniform Plumbing Code ("UPC"), that incorporate very specific regulations regarding plumbing installations. Such regulations usually specify in detail the installation necessary for enabling the proper connection of a washing machine to the hot and cold water lines and the waste system of a building. One widely used installation for this purpose utilizes a so-called washing machine outlet box. Such a box is typically molded from plastic and is installed in drywall so that it opens outwardly. Sometimes washing machine outlet boxes are made of sheet metal. A vertical drain/waste/vent ("DWV") pipe is coupled to a drain inlet opening in the center of a horizontal bottom wall of the box. The hook-shaped end of the outlet hose of the washing machine is inserted in the drain inlet opening. Hot and cold water supply pipes extend vertically through water supply holes in the bottom wall of the box on either side of the drain inlet opening. These water supply holes typically have a diameter that is substantially larger than the diameter of the water supply pipes so that the pipes are loosely mounted and are free to move laterally. Sometimes elastomeric grommets are seated in the water supply holes in the bottom wall and surround the water supply pipes. Typically a boiler drain valve with a compression type fitting is connected to the upper end of each water supply pipe. Female fittings on the ends of the hot and cold water hoses from the washing machine are screwed over the corresponding male fittings of the valves. The boiler drain valves for the hot and cold water supply can be independently turned ON and OFF by manually rotating valve handwheels.
The boiler drain valves utilized with a conventional washing machine outlet box are typically made of Brass so that they will resist corrosion. Where Copper water pipe is utilized, the end of each pipe extends through a ferrule which is seated inside a male threaded lower shank of the boiler drain valve. A compression nut is screwed tightly over the lower shank to compress the ferrule around the Copper pipe and insure a leak-proof connection. There is no need to secure the boiler drain valves directly to the bottom wall of the outlet box. This is because the Copper pipe is soldered to fittings which can withstand the torque resulting from turning the valves ON and OFF by manual rotation of the handwheels of the valves.
Recently CPVC plastic pipe has been widely utilized in residential construction. The upper ends of CPVC pipe are usually connected to standard boiler drain valves housed in a washing machine outlet box in the same manner as that described above in connection with Copper water pipe. However, in such an installation the lateral force and/or torque on the CPVC pipe which results from rotating the handwheel of a valve can weaken, damage or even break the solvent welded connection between the lower end of the CPVC pipe and a ninety degree angle CPVC fitting. This can in turn lead to water leaks behind the drywall that can result in substantial damage to the building structure. The installation of grommets that fit into the water supply holes in the bottom wall and surround the CPVC water supply pipes does not inhibit the transmission of torque to the pipes, which can damage solvent welded connections to the pipes.
In the past there have been attempts to overcome the foregoing problem of laterally moving and/or torquing of CPVC pipes connected to boiler drain valves in a washing machine outlet box. One approach has utilized a specially fabricated boiler drain valve with an extended male shank with male threads. The male shank can be inserted through the corresponding water supply hole in the bottom wall of the washing machine outlet box and secured thereto with a nut. This is a relatively expensive approach that requires a custom boiler drain valve not readily available to plumbers. Plumbers have screwed a transition fitting over the male shank of the valve in order to connect the CPVC water supply pipe to the valve. However, the transition fitting utilized has female tapered threads and was not intended to be screwed over the straight threads of the male threaded shank of the valve, which is designed for connecting Copper pipe. Therefore the joint between the transition fitting and the specially fabricated boiler drain valve frequently leaks.
Another approach to overcoming the CPVC torquing problem has utilized a standard boiler drain valve whose lower shank is screwed into a female adapter. The female adapter has an extended shank with male threads which can be inserted through the corresponding water supply hole in the bottom wall of the washing machine outlet box and secured thereto with a nut. This approach requires that a sealant be used to insure that the joint between the boiler drain valve and the female adapter is leak-proof. The sealant may be pipe joint compound or TEFLON (Trademark) sealing tape. In either case the application of the sealant adds time and cost to the installation. Furthermore, the female adapter has a lower male shank with straight threads. Once again plumbers have screwed a transition fitting over the male shank of the adapter in order to connect the CPVC water supply pipe to the adapter. However, the transition fitting utilized has female tapered threads and was not intended to be screwed over the straight threads of the male threaded shank of the adapter, which is designed for connecting Copper pipe. Therefore the joint between the transition fitting and the female adapter frequently leaks.
It is also conventional to utilize a molded plastic outlet box to mount a water supply valve in a recessed manner in a kitchen wall for connecting a water supply line to an ice maker of a refrigerator. The typical ice maker outlet box is smaller than the typical washing machine outlet box. The ice maker box encloses only one valve and has no drain. One type of valve frequently utilized in an ice maker outlet box is similar to a boiler drain valve except that instead of a male fitting for connecting a washing machine outlet hose, the valve has a compression type fitting for connecting one-quarter inch Copper or plastic tubing from the ice maker. Presently it is common practice for plumbers to install one-half inch CPVC pipe so that it extends loosely through a hole in the bottom wall of the ice maker outlet box much in the same way that CPVC pipe is conventionally connected to boiler drain valves in a washing machine outlet box. The CPVC water supply pipe is connected to the male threaded lower shank of the valve in the ice maker outlet box, but the valve is not anchored to the bottom wall of the ice maker outlet box. When the handwheel of the valve is turned, the CPVC pipe is torqued, which can weaken or damage its adhesive connection with a CVPC fitting.